You Can Have My LM386s When You Pry Them From My Cold Dead Hands

Everyone has a chip-of-shame: it’s the part that you know is suboptimal but you keep using it anyway because it just works well enough. Maybe it’s not what you would put into a design that you’re building more than a couple of, but for a quick and dirty lashup, it’s just the ticket. For Hackaday’s [Adam Fabio], that chip is the TIP120 transistor. Truth be told, we have more than one chip of shame, but for audio amplification purposes, it’s the LM386.

The LM386 is an old design, and requires a few supporting passive components to get its best performance, but it’s fundamentally solid. It’s not noise-free and doesn’t run on 3.3 V, but if you can fit a 9 V battery into your project and you need to push a moderate amount of sound out of a speaker, we’ll show you how to get the job done with an LM386.

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Daylight Saving Time – Whys And Why Nots

We recently went through our twice yearly period of communal venting called adjusting for daylight saving time (DST), or British Summer Time (BST) as it’s called in the UK. But why are we changing the time? Seriously, who caused all this? Does it do any good? Do we still need it? And what can we do about it? As it turns out, most of us want it, as you’ll see below.

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A Rebel Alliance For Internet Of Things Standards

Back when the original Internet, the digital one, was being brought together there was a vicious standards war. The fallout from the war fundamentally underpins how we use the Internet today, and what’s surprising is that things didn’t work out how everyone expected. The rebel alliance won, and when it comes to standards, it turns out that’s a lot more common than you might think.

Looking back the history of the Internet could have been very different. In the mid eighties the OSI standards were the obvious choice. In 1988 the Department of Commerce issued a mandate that all computers purchased by government agencies should be OSI compatible starting from the middle of 1990, and yet two years later the battle was already over, and the OSI standards had already lost.

In fact by the early nineties the dominance of TCP/IP was almost complete. In January of 1991 the British academic backbone network, called JANET (which was based around X.25 colored book protocols), established a pilot project to host IP traffic on the network. Within ten months the IP traffic had exceeded the levels of X.25 traffic, and IP support became official in November.

“Twenty five years ago a much smaller crowd was fighting about open versus proprietary, and Internet versus OSI. In the end, ‘rough consensus and running code’ decided the matter: open won and Internet won,”

Marshall Rose, chair of several IETF Working Groups during the period

This of course wasn’t the first standards battle, history is littered with innumerable standards that have won or lost. It also wasn’t the last the Internet was to see. By the mid noughties SOAP and XML were seen as the obvious way to build out the distributed services we all, at that point, already saw coming. Yet by the end of the decade SOAP and XML were in heavy retreat. RESTful services and JSON, far more lightweight and developer friendly than their heavyweight counterparts, had won.

“JSON appeared at a time when developers felt drowned by misguided overcomplicated XML-based web services, and JSON let them just get the job done,”

“Because it came from JavaScript, and pretty much anybody could do it, JSON was free of XML’s fondness for design by committee. It also looked more familiar to programmers.”

Simon St. Laurent, content manager at LinkedIn and O’Reilly author

Yet, depending on which standards body you want to listen to, ECMA or the IETF, JSON only became a standard in 2013, or 2014, respectively and while the IETF RFC talks about semantics and security, the ECMA standard covers only the syntax. Despite that it’s unlikely many people have actually read the standards, and this includes the developers using the standard and even those implementing the libraries those developers depend on.

We have reached the point where standardization bodies no longer create standards, they formalize them, and the way we build the Internet of Things is going to be fundamentally influenced by that new reality.

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Smartphone Bench Instrument Apps: Disappointment Or Delight?

If you are interested in electronics or engineering, you’ll have noticed a host of useful-sounding apps to help you in your design and build work. There are calculators, design aids, and somewhat intriguingly, apps that claim to offer an entire instrument on your phone. A few of them are produced to support external third-party USB instrument peripherals, but most of them claim to offer the functionality using just the hardware within the phone. Why buy an expensive oscilloscope, spectrum analyzer, or signal generator, when you can simply download one for free?

Those who celebrate Christmas somewhere with a British tradition are familiar with Christmas crackers and the oft-disappointing novelties they contain. Non-Brits are no doubt lost at this point… the crackers in question are a cardboard tube wrapped in shiny paper drawn tight over each end of it. The idea is that two people pull on the ends of the paper, and when it comes apart out drops a toy or novelty. It’s something like the prize in a Cracker Jack Box.

Engineering-oriented apps follow this cycle of hope and disappointment. But there are occasional exceptions. Let’s tour some of the good and the bad together, shall we?

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Crossing Wheatstone Bridges

The Wheatstone bridge is a way of measuring resistance with great accuracy and despite having been invented over 150 years ago, it still finds plenty of use today. Even searching for it on Hackaday brings up its use in a number of hacks. It’s a fundamental experimental device, and you should know about it.

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The Comic Book World Of Capacitor Marketing

The Economist is an interesting publication, a British weekly newspaper that looks for all the world like a magazine, and contains pithy insights into world politics and economic movements. It’s one of those rare print news publications that manages to deliver fresh insights even to hardened web news junkies despite its weekly publication date.

It was typical then of their wide-ranging coverage of world industries to publish a piece recently on the world of supercapacitors, with particular focus on Estonia’s Skeleton Technologies. This is an exciting field in which the products are inching their way towards energy density parity with conventional batteries, and news of new manufacturing facilities coming online should be of interest to many Hackaday readers.

Exciting though it may be it was not the news of a new capacitor plant in Germany that provided the impetus for this piece. Instead it was the language used by the Economist writer delicately skirting the distinction between the words “Supercapacitor” and “Ultracapacitor”. Images of flying crimefighters in brightly coloured capes spring instantly to mind, as Captain Ultra and Superman battle an arch-villain who is no doubt idly bouncing a piece of burning Kryptonite against the wall in readiness for the final denouement.

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Why You Should Own A Sewing Machine

This could probably be any of our grandmothers at work. George Grantham Bain Collection [PD], via Wikimedia Commons
This could probably be any of our grandmothers at work. George Grantham Bain Collection [PD], via Wikimedia Commons.
In our hackspace, we’ve opened a textile room in the last month. We have high hopes for it as a focal point for cosplayers and LARPers as well as the makers of wearable electronics and more traditional textile users. Putting it in has involved several months of hard work bringing a semi-derelict and previously flooded room that was once the walk-in safe for our local school authority to a point at which it is a light and welcoming space, but a surprising amount of work has also had to go into winning the hearts and minds of our community for the project.

Putting it quite simply, textiles aren’t seen as very cool, in hackspace terms. You know, Women’s stuff. Your mother does it, or even maybe if you are a little younger, your grandmother. It’s just not up there with laser cutting or 3D printing, and as a result those of us for whom it’s a big part of making stuff have had to fight its corner when it comes to resources within the space.

Yet not so long ago when I brought a pair of worn-out jeans into the space on a social night and hauled out our Lervia sewing machine to fix them, I had a constant stream of fellow members passing by amazed at what I was doing. “You can repair jeans?” they asked, incredulously. For some reason this prospect had not occurred to them, I was opening up a new vista in clothing reincarnation, to the extent that before too long in our new facility I may be giving a workshop on the subject as the beloved former trousers of Oxford Hackspace denizens gain a chance of new life.

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